Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica / Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery

Introducción: Los tumores del anillo pélvico suponen un reto por la dificultad de obtener márgenes quirúrgicos adecuados. Herramientas como la navegación quirúrgica o la impresión 3D para la fabricación de plantillas de posicionamiento quirúrgico paciente-específicas ayudan en la planificación preoperatoria y la ejecución intraoperatoria. Su correcta colocación es fundamental en localizaciones complejas como la pelvis, por lo que es necesario identificar los errores de posicionamiento. El objetivo de este estudio es demostrar la fiabilidad en la colocación de plantillas 3D para la realización de osteotomías en el anillo pélvico. Material y métodos: Estudio experimental en cadáver con 10 hemipelvis. Se realiza TC para la obtención del modelo tridimensional, planificación de osteotomías, diseño de plantillas de posicionamiento en rama isquiopubiana (I), iliopubiana (P), supracetabular (S) y cresta iliaca (C); y un marcador de posicionamiento (rigid-body) sobre las plantillas C y S para la navegación. Las plantillas y el rigid-body son impresos en 3D y se colocan según planificación previa. La navegación permite comprobar la posición final de las plantillas y de las osteotomías. Resultados: El posicionamiento de las plantillas respecto a la planificación preoperatoria varió dependiendo de la localización, siendo mayor el error en las de cresta iliaca. Utilizando la navegación, la media de error de distancia al plano de corte está en 3,5mm, excepto en pubis (5-8mm), estando condicionado por la posición del rigid body. Conclusión: El uso de plantillas paciente-específicas impresas en 3D es una herramienta fiable para la realización de osteotomías en cirugía oncológica pélvica.(AU)

Introduction: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. Material and methods: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. Results: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis 5-8mm), being conditioned by the position of the rigid body. Conclusion: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.(AU)

[Translated article] Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery / Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica

Introducción: Los tumores del anillo pélvico suponen un reto por la dificultad de obtener márgenes quirúrgicos adecuados. Herramientas como la navegación quirúrgica o la impresión 3D para la fabricación de plantillas de posicionamiento quirúrgico paciente-específicas ayudan en la planificación preoperatoria y la ejecución intraoperatoria. Su correcta colocación es fundamental en localizaciones complejas como la pelvis, por lo que es necesario identificar los errores de posicionamiento. El objetivo de este estudio es demostrar la fiabilidad en la colocación de plantillas 3D para la realización de osteotomías en el anillo pélvico. Material y métodos: Estudio experimental en cadáver con 10 hemipelvis. Se realiza TC para la obtención del modelo tridimensional, planificación de osteotomías, diseño de plantillas de posicionamiento en rama isquiopubiana (I), iliopubiana (P), supracetabular (S) y cresta iliaca (C); y un marcador de posicionamiento (rigid-body) sobre las plantillas C y S para la navegación. Las plantillas y el rigid-body son impresos en 3D y se colocan según planificación previa. La navegación permite comprobar la posición final de las plantillas y de las osteotomías. Resultados: El posicionamiento de las plantillas respecto a la planificación preoperatoria varió dependiendo de la localización, siendo mayor el error en las de cresta iliaca. Utilizando la navegación, la media de error de distancia al plano de corte está en 3,5mm, excepto en pubis (5-8mm), estando condicionado por la posición del rigid body. Conclusión: El uso de plantillas paciente-específicas impresas en 3D es una herramienta fiable para la realización de osteotomías en cirugía oncológica pélvica.(AU)

Introduction: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. Material and methods: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. Results: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis 5-8mm), being conditioned by the position of the rigid body. Conclusion: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.(AU)

[Translated article] Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery.

INTRODUCTION: Pelvic ring tumours pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

Validation of patient-specific 3D impression models for pelvic oncological orthopedic surgery. / Validación de los modelos de impresión 3D paciente-específicos para cirugía ortopédica oncológica pélvica.

INTRODUCTION: Pelvic ring tumors pose a challenge due to the difficulty in obtaining adequate surgical margins. Tools such as surgical navigation or 3D printing for the fabrication of patient-specific surgical positioning templates help in preoperative planning and intraoperative execution. Their correct positioning is essential in complex locations such as the pelvis, so it is necessary to identify positioning errors. The aim of this study is to demonstrate the reliability of 3D template placement for pelvic ring osteotomies. MATERIAL AND METHODS: Experimental study in cadaver with 10 hemipelvis. CT was performed to obtain the three-dimensional model, planning of osteotomies, design of positioning templates in ischiopubic (I), iliopubic (P), supracetabular (S) and iliac crest (C) branches; and a positioning marker (rigid-body) on the C and S templates for navigation. The templates and rigid-body are 3D printed and positioned according to pre-planning. Navigation allows the final position of the inserts and osteotomies to be checked. RESULTS: The positioning of the templates with respect to the preoperative planning varied depending on the location, being greater the error in those of the iliac crest. Using navigation the mean error of distance to the cutting plane is 3.5mm, except in pubis (5-8mm), being conditioned by the position of the rigid body. CONCLUSION: The use of patient-specific templates printed in 3D is a reliable tool for performing osteotomies in pelvic cancer surgery.

The knee prosthesis constraint dilemma: Biomechanical comparison between varus-valgus constrained implants and rotating hinge prosthesis. A cadaver study.

The real degree of constriction of rotating hinge knee (RHK) and condylar constrained prostheses (CCK) is a matter of discussion in revision knee arthroplasty. The objectives of this study are to compare the tibial rotation of both implants and validate the use of inertial sensors with optical tracking system as movement measurement tools. A total of 16 cadaver knees were used. Eight knees were replaced using a RHK (Endomodel LINK), and the remaining eight received a CCK prosthesis (LCCK, Zimmer). Tibial rotation range of motion was measured in full extension and at 30°, 60°, and 90° of flexion, with four continuous waveforms for each measurement. Measurements were made using two inertial sensors with specific software and compared with measurements obtained using the gold standard technique - the motion capture camera. The comparison of the accuracy of both measurement methods showed no statistically significant differences between inertial sensors and motion capture cameras, with p > .1; the mean error for tibial rotation was 0.21°. Tibial rotation in the RHK was significantly greater than in the CCK (5.25° vs. 2.28°, respectively), p < .05. We have shown that RHK permit greater tibial rotation, being closer to physiological values than CCKs. Inertial sensors have been validated as an effective and accurate method of measuring knee movement. The clinical significance: RHK appears to represent a lower constriction degree than CCK systems.

[Articular irrigation in arthroscopy]. / L'irrigation articulaire en arthroscopie.

Synovial oedema is a frequent complication in arthroscopic procedures performed with normal saline as the irrigating fluid. The authors have studied the effect of saline solution, Ringer lactate, 5% Dextran and 10% Dextran in normal saline on 12 specimens of human synovial membrane. They found that 10% Dextran in normal saline decreases the water content of the synovium without causing damage, and recommend this solution for procedures lasting longer than 30 minutes.

L'irrigation articulaire en arthroscopie : Articular irrigation in arthroscopic procedures.

Synovial oedema is a frequent complication in arthroscopic procedures performed with normal saline as the irrigating fluid. The authors have studied the effect of saline solution, Ringer lactate, 5% Dextran and 10% Dextran in normal saline on 12 specimens of human synovial membrane. They found that 10% Dextran in normal saline decreases the water content of the synovium without causing damage, and recommend this solution for procedures lasting longer than 30 minutes.